We're using EPiServer CMS 5.2.375.7. When browsing the File manager it crashes at certain locations. The error is the usual "Object reference not set.." which fails when trying to get the file version summary. I've logged this issue with EPiServer and got a response, but they don't know what is causing this. Anyone else got this problem or know why this is happening? We've managed to get rid of the problematic files, but now the problem is occurring on a daily basis.
From Episerver support:
We have seen this error before in few cases and in that it happend due to a file without any versioncounter set and no defualtversion. However we dont have any information how such file can exist so we were unable to reproduce the issue.
So we know how to solve the issue and for this we would need your DB or if its not possible then we have an internal tool(Windmill Explorer ) that can be used to find out what file that's causing this error and remove it. Just follow these instructions and you should be able to fix it:
Be wary when using windmill explorer. It's an unsupported tool that you can make serious damage to your database. Make sure to grab a backup of your database before using the tool.
By using the application windmill explorer we can browse the object store and locate what file is causing the error. In the filesystem, browse to the folder that is getting the above error. Look for a file with _versionCounter = 0.